Abstract Rationale Agent Orange exposure has been linked to increased risks of several malignancies, including lung cancer. However, its relationship with lung cancer screening (LCS) uptake among eligible Veterans remains unknown. Clarifying this association may inform strategies to promote screening in high-risk populations. Methods We constructed a cohort of LCS-eligible VA primary care patients during 1/1/2015-9/30/2023 who were deemed healthy enough for LCS by their provider as documented in the LCS clinical reminder. We excluded patients in hospice/palliative care or with prior lung cancer. LCS was identified through a validated approach to distinguish screening from diagnostic tests. Agent Orange exposure and covariate information was extracted from the Corporate Data Warehouse (CDW). Multivariable logistic regression assessed the association between Agent Orange exposure and LCS uptake adjusted for the following pre-specified covariates: age (years), sex (male/female), marital status (married/not married), BMI (18.5, 18.5 to 25, 25 to 30, or 30+), tobacco cigarette pack-years (years), receipt of influenza vaccine in prior 12 months (yes/no), race (White/Black/not White, not Black), ethnicity (Hispanic or Latino, not Hispanic or Latino), rural (yes/no). Results Among 171,686 Veterans (mean age 65.6 years; 93% male; 78% White, 13% Black, and 8.5% Other), Lung cancer screening use was missing for 2774 individuals (1.62%). A total of 70,047 individuals (40.8%) completed LCS. Among the entire cohort, 25,156 Veterans (14.7%) reported Agent Orange exposure. In the unadjusted analysis, screening uptake was slightly lower among exposed Veterans (38.5%, 95% CI: 37.9-39.1%) compared to unexposed (42.0%, 95% CI: 41.7-42.2%). In the fully adjusted model, Agent Orange exposure was associated with higher screening odds (adjusted Odds Ratio (OR)=1.11, 95% CI: 1.08-1.15; Table 1), with age and sex driving the change (OR adjusted for age and sex only=1.12, 95% CI:1.09-1.16). Conclusions Agent Orange exposure was common among LCS-eligible VA patients and modestly increased the chance of screening after adjustment for age, sex, and other confounders. As lung cancer screening moves towards risk-based approaches to identify individuals most likely to benefit from screening, considering exposures such as Agent Orange may be important to identify patients at high lung cancer risk who are less likely to be screened for lung cancer. Future research should explore whether risk perception or awareness of the carcinogenic potential of Agent Orange plays a role in screening behavior in this population. This abstract is funded by: This research was partially funded by the Career Development Award (CX002713) from the United States (U.S.) Department of Veterans Affairs Clinical Science Research and Development Service (Dr. Rustagi). Additional support for Dr. Rustagi came from the National Institute on Aging (1R03AG082924), VA’s Lung Precision Oncology Program, and the Early Career Award Program from VA’s VISN21. The sponsors of the study did not participate in the study design; collection, analysis, or interpretation of data; writing the report; or the decision to submit the manuscript for publication. The study received approval from the Human Research Protection Program at the University of California, San Francisco and the San Francisco VA Health Care System (IRB 24-41009), in accordance with all relevant regulations. The opinions expressed herein are those of the authors and not their employers, the U.S. Department of Veterans Affairs, the U.S. government, or the study sponsors.
Alvarez et al. (Fri,) studied this question.